Improvement in rotary blowers



r. r1. noors,

OF CONNERSVILLE, INDIANA.

IMPROVEMENT IN ROTARY BLOWERS.

Specification forming part of Letters Patent No. 58,745, dated October9, 1866.

To all 'whom t may concern:

Be it known that I, I). H.Boo1s,of Gonnersville, in the county ofFayette and State of Indiana, have invented a new and useful Improvementin Rotary Blowers; and I do herebydeclare that the following is a full,clear, and exact description thereof, which will enable others skilledin the art to make and use the same, reference being had to theaccompanying drawings, forming part of this specification, in which-Figure l represents a longitudinal vertical section of this invention.Fig. 2 is a plan or top view of the same. Fig. 3 is a diagramillustrating the construction of the pistons.

Similar letters of reference indicate like parts.

This invention relates to an improvement in that class of rotary blowerson which a patent has been granted to me September 25, 1860.

The object of this present improvement is to modify in any desireddegree the proportion of the pistons and recesses of said rotaryblowers, which, in the above-named patent, are formed of arcs whosechords are of equal length.

According to my present improvement the arc of the recesses is reducedand that of the pistons is increasedthat is to say, the pistons andrecesses are described with the same radius, but the pistons comprise anarc greater than that of the recesses; and my experience shows that theeffect of the pump is not impaired by this change in the form of thepistons and recesses, but on the contrary a bencicial result is attainedin causing the coacting pistons of the respective abutments to lapinstead of simply meeting at their corners, as described in my formerpatent.

Aand B represent two double-acting rotating abutments, alike in allrespects, each having two or more pistons, D D, and two or :morerecesses, E E. Said abutments are mounted on shafts@ C, and they areplaced in such a position in relation to each other that the pistons ofone abutment work or gear in the recesses of the other abutment, andvice versa, as clearly shown in Fig. l of the drawings.

The method in which the pistons and recesses are constructed will bereadily understood by referring to the diagram shown in Fig. 3 of thedrawings. From the centers of the shafts C C', I describe two circles, cc', which do not touch each other,the distance between their peripheriesbeing more or less, according to the degree of reductionv desired inthelength of arc of the recesses. I then connect the centers of these twocircles by a right line, b c, and erect thereon perpendicular lines d cd e', passing through the centers of the circles c c. I then nd a point,f, in the periphery of the circle a which is equidistant from the pointof,intersection g between the perpendicular line d e and the peripheryof the circle a', and from the point of intersection 7L between the linec d and the periphery of the circle c and the lines gf and hfform theradii-one for the piston D and the other for the recesses E.

It will be readily seen that by these means the arcs of the pistonscomprise more than a quarter-circle, and the arcs of the recesses lessthan a quarter-circle, 011 the inscribed circles a and a; and,furthermore, by increasing the distance between the peripheries of thecircles c c in proportion to their diameters the depth of the recessesis reduced. How far this reduction can be carried on without interferingwith the practical effect of the blower must be found out byexperiments; but according to my present experience I am well satisfiedthat the recesses may be reduced to a considerable extent withoutimpairin g the correct movements of the abutments, but a materialreduction would considerably diminish the capacity of the blower forexpelling air.

In the above description I have selected to illustrate my inventionabutments having each two pistons and two recesses; but it is evidentthat the invention is equally applicable to any number.

It must be distinctly understood that I disclaim everything describedand contained in my aforesaid patent of September 25, 1860, and alsoeverything contained in the patent of David M. Talker, 1835.

What I claim as new, and desire to secure by Letters Patent, is

l. The rotating abutments A B, each constructed with two or morepistons, D, and 2. Finding the centers and radii for the pisrecesses E,constituting arcs of equal radius, tons and recesses of the rot-aryabutments A but Whose chords are of unequal length, the B in the mannerdescribed with reference to chords of the arcs of the pistons D bein gmade Fig. 3 of the drawings.

of greater length than those of the recesses I?. H. ROOTS. E, so as tocanse the coacting pistons to lap Witnesses:

at and near the angles7 substantially as herein WM. F. MGNAMARA,described. ALEX. F. ROBERTS.

